Issued by NWS Indianapolis, IN
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000 FXUS63 KIND 260535 AFDIND AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE INDIANAPOLIS IN 135 AM EDT SUN OCT 26 2008 .DISCUSSION... FOCUS WL BE ON THE SHORT TERM ESPECIALLY REGARDING WIND POTENTIAL AND TEMPS. CLEAR SKIES SEEN ON IR IMAGERY ACRS CNTRL INDIANA EARLY THIS AM. MID LVL DECK ACRS SRN MN AND IA WAS MARKING THE LEADING EDGE OF THE 130KT UPR LVL JET THAT WAS PLUNGING SE IN THE CYCLONIC FLOW. FINALLY...THE STG CD FNT EXTENDED FM CNTRL MN TO THE SD/NE BORDER AT 04Z. MODELS IN VERY GOOD AGREEMENT ON BRINGING THE STG CD FNT ACRS CNTRL INDIANA IN THE 12Z-18Z TIME FRAME TODAY. 45KT BOUNDARY LYR WINDS ARE SHOWING UP ON THE LAF MODEL SOUNDINGS WITH PLNTY OF MIXING EXPECTED. FURTHER S...MODEL SOUNDINGS ARE NOT QUITE AS IMPRESSIVE REGARDING THE BOUNDARY LYR WINDS...SO WL KEEP WIND ADVISORY WHERE IT IS ROUGHLY JUST N OF A HUF TO IND LINE. GUSTY WINDS WL CONTINUE AFTER DARK...BUT WL DROP OFF BLW ADVISORY CRITERIA WITH THE LOSS OF THE SS. MODELS ARE SIMILAR IN BRINGING POST FRONTAL LOW LVL MOISTURE ASSOCIATED CURRENT SC ACRS SCNTRL CANADA AND NRN MN SE ACRS THE FA TOWARD 12Z MONDAY AND CONTINUING THROUGH THE DAY. KEPT THE REST OF THE FCST DRY. UPR RIDGE WL APPROACH LATE IN THE WEEK WHICH SHOULD PROVIDE FOR A DECENT WARMUP. STG POST FRONTAL CAA SHOULD STUNT TEMPS THIS AFTERNOON...SO AGREE WITH RELATIVE LOW MOS TEMPS TODAY. WL LEAN TOWARD LOW END OF GUIDANCE TNGT WITH STG CAA CONTINUING AND DESPITE WINDS STAYING UP. FINALLY...WITH 850 MB TEMPS MINUS 7 CELSIUS ON MONDAY AND LOTS OF SC...WL GO AOB MOS. && .AVIATION...DISCUSSION FOR 260600Z TAFS. VFR THROUGH THE TAF PERIOD. MAIN CONCERN WILL BE LOW LEVEL WIND SHEAR UNTIL 12Z AND SFC WIND GUSTS IN EXCESS 30 KNOTS LATER TODAY. STRONG LOW PRESSURE WAS NORTH OF LAKE SUPERIOR AND A DRY COLD FRONT EXTENDED TO THE CENTRAL PLAINS. SATELLITE SHOWS MOSTLY CLEAR SKIES AROUND INDIANA...BUT MID CLOUDS OVER IOWA AND SOUTH DAKOTA WILL MOVE RAPIDLY OUR WAY BY MORNING. VWP INDICATE WINDS AS HIGH AS 50 KNOTS 2000 FEET ABOVE GROUND ACROSS NORTHERN ILLINOIS AND MODEL SOUNDINGS WINDS ALMOST 50 KNOTS ARE POSSIBLE AT KLAF AND KIND AFTER 06Z. SO WILL MENTION LOW LEVEL WIND SHEAR AT THOSE SITES. MODELS INDICATE WIND SHEAR DIMINISHING RAPIDLY SUNDAY MORNING AS BETTER MIXING OCCURS. DRY COLD FRONT WILL MOVE THROUGH CENTRAL INDIANA AROUND MIDDAY SUNDAY WITH GUSTS IN EXCESS OF 30 KNOTS AT KLAF AND KIND. GRADIENT GRADUALLY DIMINISHING AFTER 23Z SUNDAY. && .PREV DISCUSSION... FCST FOCUS ON WINDS AND TEMPS. UPPER TROUGH IS LIFTING NE AWAY FROM THE REGION WHILE A STRONG UPPER JET IS DIVING INTO THE CENTRAL PLAINS. A STRONG COLD FRONT WAS LOCATED ACROSS ACROSS ND INTO MT WITH A INITIAL PACIFIC COLD FRONT WAS LOCATED ACROSS MN INTO KS. GUIDANCE IS AGAIN IN REASONABLE AGREEMENT WITH REGARD TO BASIC FEATURES THROUGH THE WEEKEND INTO EARLY NEXT WEEK. WE WILL LEAN TOWARD A BLEND FOR MAX TEMPS SUN AND COLDER THAN ALL GUIDANCE MON/TUES. NO CHANGES ARE PLANNED BEYOND WEDS. TONIGHT/SUN...STRONG WAA WILL DEVELOP ALOFT AS THE INTENSE UPPER AND MID JET APPROACH. TEMPS ARE ALREADY COOL THIS AFTERNOON AND WILL ONLY HAVE TO FALL SEVERAL DEGREES TO REACH GOING LOWS. FEEL THAT OVERNIGHT TEMPS MAY BECOME STEADY AFTER MIDNIGHT. BY SUN...850MB THERMAL RIDGE WILL SLIDE QUICKLY ACROSS THE REGION WITH THE COLD FRONT AT 850MB FCST TO SURGE INTO THE AREA BY MIDDAY PROVIDING CAA ALOFT AND LIMITING HIGHS. ROUGH ESTIMATE OF HIGHS BASED OFF OF A MAX MIX TO 850MB SUGGEST UPPER 50S NORTH TO MID 60S SOUTH. WINDS ATOP THE MIXING LAYER BY MIDDAY WILL APPROACH 40KTS WITH THE STRONGEST WINDS FCST TO OCCUR ACROSS THE NORTH. WE WILL ISSUE A WIND ADVISORY FOR SUN ACROSS THE NORTH AND LET LATER SHIFTS EVALUATE WHETHER THIS NEEDS TO BE ADJUSTED. SUN NIGHT/MON...ACTUAL SFC COLD FRONT WILL ARRIVE BETWEEN 00Z AND 03Z MON WHICH WILL LEAD TO ANOTHER BURST OF GUSTY WINDS. STRONG CAA WILL OCCUR AND DESPITE THE MIXING WE STILL EXPECT LOWS TO DROP TOWARD 30 DEGREES. HIGHS MON BASED OFF OF 850MB TEMPS SUGGEST MID 40S AT BEST BOTH MON AND TUES SO WILL LOWER FCST NUMBERS TO BELOW GUIDANCE. AS MENTIONED...NO CHANGES TO THE EXTENDED BEYOND TUES WITH A GRADUAL WARMING TREND BACK TOWARD OR ABOVE AVG FOR DAYTIME HIGHS BY THU/FRI. && .IND WATCHES/WARNINGS/ADVISORIES...WIND ADVISORY NORTHERN THIRD TODAY. && $$ AVIATION...JH/CP PUBLIC...MK